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The goal of this study is to evaluate a version of the ensemble-variational data assimilation approach (EnVar) for possible replacement of 4D-Var at Environment Canada for global deterministic weather prediction. This implementation of EnVar relies on 4-D ensemble covariances, obtained from an ensemble Kalman filter, that are combined in a vertically dependent weighted average with simple static covariances. Verification results are presented from a set of data assimilation experiments over two separate 6-week periods that used assimilated observations and model configuration very similar to the currently operational system. To help interpret the comparison of EnVar versus 4D-Var, additional experiments using 3D-Var and a version of EnVar with only 3-D ensemble covariances are also evaluated. To improve the rate of convergence for all approaches evaluated (including EnVar), an estimate of the cost function Hessian generated by the quasi-Newton minimization algorithm is cycled from one analysis to the next. Analyses from EnVar (with 4-D ensemble covariances) nearly always produce improved, and never degraded, forecasts when compared with 3D-Var. Comparisons with 4D-Var show that forecasts from EnVar analyses have either similar or better scores in the troposphere of the tropics and the winter extra-tropical region. However, in the summer extra-tropical region the medium-range forecasts from EnVar have either similar or worse scores than 4D-Var in the troposphere. In contrast, the 6 h forecasts from EnVar are significantly better than 4D-Var relative to radiosonde observations for both periods and in all regions. The use of 4-D versus 3-D ensemble covariances only results in small improvements in forecast quality. By contrast, the improvements from using 4D-Var versus 3D-Var are much larger. Measurement of the fit of the background and analyzed states to the observations suggests that EnVar and 4D-Var can both make better use of observations distributed over time than 3D-Var. In summary, the results from this study suggest that the EnVar approach is a viable alternative to 4D-Var, especially when the simplicity and computational efficiency of EnVar are considered. Additional research is required to understand the seasonal dependence of the difference in forecast quality between EnVar and 4D-Var in the extra-tropics.

In 2003, strong energetic particle precipitation (EPP) events occurred producing massive amounts of ionization which affected the polar region significantly perturbing its chemical state down to the middle stratosphere. These events and their effects are generally left unaccounted for in current models of stratospheric chemistry and large differences between observations and models are then noted. In this study, we use a coupled 3-D stratospheric dynamical-chemical model and assimilation system to ingest MIPAS temperature and chemical observations. The goal is to gain further understanding of assimilation and monitoring processes during EPP events and their impacts on the stratospheric polar chemistry. Moreover, we investigate the feasibility of assimilating valid "outlier" observations associated with such events. We use OmF (Observation minus Forecast) residuals as they filter out phenomena well reproduced by the model (such as gas phase chemistry, transport, diurnal and seasonal cycles) thus revealing a clear trace of the EPP. Inspection of OmF statistics in both passive (without chemical assimilation) and active (with chemical assimilation) cases altogether provides a powerful diagnostic tool to assess the model and assimilation system. We also show that passive OmF can permit a satisfactory evaluation of the ozone partial column loss due to EPP effects. Results suggest a small but significant loss of 5–6 DU (Dobson Units) during an EPP-IE (EPP Indirect Effects) event in the Antarctic winter of 2003, and about only 1 DU for the SPE (Solar Proton Event) of October/November 2003. Despite large differences between the model and MIPAS chemical observations (NO2, HNO3, CH4 and O3), we demonstrate that a careful assimilation with only gas phase chemistry included in the model (i.e. no provision for EPP) and with relaxed quality control nearly eliminated the short-term bias and significantly reduced the standard deviation error of the constituents below 1 hPa.

Background: Exoskeletons are used in rehabilitation centers for people with spinal cord injuries (SCI) due to the potential benefits they offer for locomotor rehabilitation. The acceptability of exoskeletons is crucial to promote rehabilitation and to ensure a successful implementation of this technology. The objective was to explore the acceptability of overground wearable powered exoskeleton used in rehabilitation among people with SCI. Methods : Fourteen individuals with SCI (9 men, mean [SD] age 47 years [14.8], a majority with traumatic and thoracic lesion (T6-T12)) who had utilized an exoskeleton in Canada or in France during their rehabilitation participated in a semi-structured interview. A thematic analysis using the theoretical framework of acceptability was carried out. Results : Participants were motivated to use an exoskeleton during their rehabilitation. They reported several perceived benefits to its use, including better walking pattern, increased endurance, and greater muscle mass. They also experienced mild pain, notable concentration demands, and fatigue. Most participants reported that using exoskeletons in their rehabilitation process was appropriate and relevant to them. Conclusions : Exoskeletons are generally well accepted by participants in this study. Adjustments in their use, such as conducting training sessions in obstacle-free environment and technological improvements to address the device's restrictive characteristics, heaviness, and massiveness are however still needed.

Background: In Canada, primary care reforms led to the implementation of various team-based care models to improve access and provide more comprehensive care for patients. Despite these advances, ongoing challenges remain. The aim of this scoping review is to explore current understanding of the functioning of these care models as well as the contexts in which they have emerged and their impact on the population, providers and healthcare costs., Methods: The Medline and CINAHL databases were consulted. To be included, team-based care models had to be co-located, involve a family physician, specify the other professionals included, and provide information about their organization, their relevance and their impact within a primary care context. Models based on inter-professional intervention programs were excluded. The organization and coordination of services, the emerging contexts and the impact on the population, providers and healthcare costs were analysed., Results: A total of 5952 studies were screened after removing duplicates; 15 articles were selected for final analysis. There was considerable variation in the information available as well as the terms used to describe the models. They are operationalized in various ways, generally consistent with the Patient's Medical Home vision. Except for nurses, the inclusion of other types of professionals is variable and tends to be associated with the specific nature of the services offered. The models primarily focus on individuals with mental health conditions and chronic diseases. They appear to generally satisfy the expectations of the overarching framework of a high-performing team-based primary care model at patient and provider levels. However, economic factors are seldom integrated in their evaluations., Conclusions: The studies rarely provide an overarching view that permits an understanding of the specific contexts, service organization, their impacts, and the broader context of implementation, making it difficult to establish universal guidelines for the operationalization of effective models. Negotiating the inherent complexity associated with implementing models requires a collaborative approach between various stakeholders, including patients, to tailor the models to the specific needs and characteristics of populations in given areas, and reflection about the professionals to be included in delivering these services., (© 2024. The Author(s).)

Purpose: Multiple healthcare professionals fit walking aids (WA) and train individuals on their use. The purpose of this investigation was to describe curricula on WA fitting and training in Canadian entry-to-practice professional programs., Materials and Methods: An online survey was administered to leads from all accredited programs ( n  = 199). Seventeen questions asked about the importance of WA education, instructional methods and time dedicated to WA fitting and skills training, and how the pandemic had affected WA curriculum delivery., Results: Responses were received from 97 programs. While most occupational therapy (OT, 8/15), physiatry (PM&R, 5/9), and physical therapy (PT, 12/19) trainees received more than 3 h of instruction on WA fitting, most nursing (29/40) and pharmacy (7/8) programs spent less than 3 h on this topic. Most OT (9/15) and PT (15/19) programs spent more than 3 h on WA skills training whereas most nursing (25/40), pharmacy (4/8), and PM&R (5/9) programs spent less than 3 h on this subject. Across all programs, 52% educated students on adapting activities of daily living for WA while 18% provided education on WA maintenance and repair. Only 19/89 programs consulted a formal WA skills training resource for curriculum development. Seventeen of 55 programs modified their WA curricula due to the pandemic., Conclusions: There is a wide range in curricular approaches to WA education in Canadian professional programs. This highlights the need for a standardised WA education program to guide curricular development to ultimately improve safe WA use for clients with short- and long-term mobility impairments.IMPLICATIONS FOR REHABILITATIONCurricula on walking aids is extremely variable within and between programs.Navigating terrains, adapting activities of daily living, and maintenance are poorly taught.There is a need for a national standardized curriculum on walking aids.This curriculum should be modular and designed for practitioners, students, and patients.

Background: Wearable powered exoskeletons represent a promising rehabilitation tool for locomotor training in various populations, including in individuals with a spinal cord injury. The lack of clear evidence on how to implement a locomotor powered exoskeleton training program raises many challenges for patients, clinicians and organizations., Objective: To report determinants of implementation in clinical practice of an overground powered exoskeleton locomotor training program for persons with a spinal cord injury., Data Sources: Medline, CINAHL, Web of Science., Study Selection: Studies were included if they documented determinants of implementation of an overground powered exoskeleton locomotor training program for individuals with spinal cord injury., Data Extraction: Eligible studies were identified by two independent reviewers. Data were extracted by one reviewer, based on constructs of the Consolidated Framework for Implementation Research, and validated by a second reviewer., Results: Sixty-three articles were included. 49.4% of all determinants identified were related to the intervention characteristics, 29.6% to the individuals' characteristic and 13.5% to the inner setting. Recurrent barriers identified were the high prevalence of adverse events (e.g., skin issues, falls) and device malfunctions. Adequate training for clinicians, time and resource available, as well as discussion about patients' expectations were identified as facilitators., Conclusions: Powered exoskeleton training is a complex intervention. The limited information on the context and the implementation process domains may represent a barrier to a successful transition from knowledge to action.

Despite decades of research establishing the importance of breastfeeding, skin-to-skin contact and mother-infant closeness, the response to the coronavirus disease 2019 (COVID-19) pandemic has underscored the hidden assumption that these practices can be dispensed with no consequences to mother or child. This article aims to support shared decision-making process for infant feeding and care with parents and health care providers during the unprecedented times of the pandemic. It proposes a structure and rationale to guide the process that includes (1) discussing with parents evidence-based information and the different options to feed and care for an infant and young child in the context of the pandemic as well as their potential benefits, risks and scientific uncertainties; (2) helping parents to recognize the sensitive nature of the decisions and to clarify the value they place on the different options to feed and care for their infant or young child; and (3) providing guidance and support needed to make and implement their decisions. A shared decision-making process will help parents navigate complex feeding and care decisions for their child as we face the different stages of the COVID-19 pandemic., (© 2021 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.)

This paper presents the Mechanical Ventilator Milano (MVM), a novel intensive therapy mechanical ventilator designed for rapid, large-scale, low-cost production for the COVID-19 pandemic. Free of moving mechanical parts and requiring only a source of compressed oxygen and medical air to operate, the MVM is designed to support the long-term invasive ventilation often required for COVID-19 patients and operates in pressure-regulated ventilation modes, which minimize the risk of furthering lung trauma. The MVM was extensively tested against ISO standards in the laboratory using a breathing simulator, with good agreement between input and measured breathing parameters and performing correctly in response to fault conditions and stability tests. The MVM has obtained Emergency Use Authorization by U.S. Food and Drug Administration (FDA) for use in healthcare settings during the COVID-19 pandemic and Health Canada Medical Device Authorization for Importation or Sale, under Interim Order for Use in Relation to COVID-19. Following these certifications, mass production is ongoing and distribution is under way in several countries. The MVM was designed, tested, prepared for certification, and mass produced in the space of a few months by a unique collaboration of respiratory healthcare professionals and experimental physicists, working with industrial partners, and is an excellent ventilator candidate for this pandemic anywhere in the world., (© 2021 Author(s).)

Background: Older adults are at greater risk of falls while descending stairs. Cognitive deficits can further influence one's ability and mild cognitive impairments (MCI) specifically affect visual attention and dual tasking behavior. The present study aimed at comparing the attentional costs at different points during the approach to and descent of a staircase between older adults with and without MCI., Methods: Eleven older adults with MCI and twenty-three healthy older individuals without cognitive impairments were recruited. Neuropsychological tests were carried out. In addition, participants approached and descended a 5-step staircase while a simultaneous visual Stroop dual-task was randomly introduced during the approach, transition or steady state descent phases across trials. Three-dimensional kinematics and accuracy on the Stroop task were analyzed and dual task costs were calculated., Results: The MCI group showed deficits for visuo-spatial attention, memory and multi-tasking abilities, as well as balance and decreased confidence for falls efficacy, but not for daily activity scores. Despite such changes, this group of community-dwelling individuals with MCI presented a functional capacity to descend stairs even during divided visual attention. However, there were subtle, but significant, group differences for movement fluidity and performance on the simultaneous cognitive task, particularly during the approach and transition to descent phases. The MCI group also tended to descend slower while using the handrails more than healthy older adults., Conclusion: The present cohort of community-dwelling older adults with MCI were functional, but appeared to prioritize locomotor demands over the simultaneous cognitive task in a possible "posture first" strategy to descend stairs. The present findings should be considered for developing more ecologically based clinical assessments of mobility deficits following cognitive impairments, with the approach and transition phases during stair descent as key points of focus., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: To determine the possible relationship between pain experienced by mothers with breastfeeding and musculoskeletal impairment commonly seen in physiotherapy practice. Evidence-based principles of the evaluation and treatment of musculoskeletal impairment used in physiotherapy practice were applied and adapted to manage pain experienced by mothers with breastfeeding. Subjects and Methods: This report describes 11 mothers referred to a breastfeeding clinic for pain with breastfeeding. Mothers were initially assessed by a physician and a nurse clinician, both International Board-Certified Lactation Consultants, to rule out causes of breast or nipple pain. When the cause remained unexplained, it was deemed musculoskeletal, and mothers were referred to a physiotherapist for assessment and treatment with manual orthopedic therapy and mobilization of the myofascial system. Results: The physiotherapist's objective musculoskeletal assessment and mothers' impression showed an improvement in the overall clinical picture after the first appointment in most mothers. Pain was resolved or alleviated by 80% in five mothers after 1-3 weekly treatments. The most useful therapeutic approach was to make afflicted mothers aware of their posture to maintain spinal alignment and avoid shear posture (lateral displacement of the trunk). Shear posture is a consequence of sitting leaning to one side. This posture is exacerbated by thoracic rotation and flexion, for example, when turning the trunk and bending over the baby while giving the breast. Conclusion: Treating musculoskeletal impairment referred pain to the breast or nipple with physiotherapy practices used in a nonbreastfeeding clientele can help alleviate or resolve pain with breastfeeding.

Objective: To understand family physicians' perceptions of Manitoba's strategies for primary care renewal or reform (PCR)., Design: Qualitative substudy of an explanatory case study., Setting: Rural and urban Manitoba., Participants: A total of 60 family physicians (31 fee-for-service physicians, 26 alternate-funded physicians, and 3 physicians representing provincial physician organizations)., Methods: Semistructured interviews and focus groups., Main Findings: Many physicians were hesitant to participate in PCR initiatives, perceiving clear risks but uncertain benefits to patients and providers. Additional barriers to participation included concerns about the adequacy and import of communication about PCR, the meaningfulness of opportunities for physician "voice," and the trustworthiness of decision makers. There was an appetite for tailored, clinic-level support in addressing concrete, physician-identified problems; however, the initiatives on offer were not widely viewed as providing such support., Conclusion: Although some of the observed barriers might fade over time, concentrating PCR efforts on the everyday realities of family physician practice might be the best way to build a primary care system that works for patients and providers., (Copyright© the College of Family Physicians of Canada.)

Primary care reform cannot succeed without substantive change on the part of providers. In Canada, these are mostly fee-for-service physicians, who tend to regard themselves as independent professionals and not under managerial sway. Hence, policymakers must balance two conflicting imperatives: ensuring the acceptability of renewal efforts to these physicians while enforcing their accountability for defined actions or outcomes. In its 2011-15 strategy to improve access to primary care, the province of Manitoba introduced several linked initiatives, each striving to blend acceptability- and accountability-promoting elements. Clearly delimited initiatives that directly promoted a specific observable behaviour (accountability) through financial or non-financial support (acceptability) were most successfully implemented. System-wide initiatives with complicated designs (notably a primary care network model that established formal partnership among clinics and regional health authorities) encountered greater difficulties in recruiting and sustaining physician participation. Although such initiatives offered physicians considerable decision-making latitude (acceptability), many physicians questioned the meaningfulness of opportunities for voice within a predetermined structure (accountability). Moreover, policymakers struggled to enhance the acceptability of such initiatives without sacrificing strong accountability mechanisms. Policymakers must carefully consider how acceptability and accountability elements may interact, and design them in such a way as to minimize the risk of mutual interference., (Copyright © 2019. Published by Elsevier B.V.)

Purpose: Healthcare policymakers and managers struggle to engage private physicians, who tend to view themselves as independent of the system, in new models of primary care. The purpose of this paper is to examine this issue through a social identity lens., Design/methodology/approach: Through in-depth interviews with 33 decision-makers and 31 fee-for-service family physicians, supplemented by document review and participant observation, the authors studied a Canadian province's early efforts to engage physicians in primary care renewal initiatives., Findings: Recognizing that the existing physician-system relationship was generally distant, decision-makers invested effort in relationship-building. However, decision-makers' rhetoric, as well as the design of their flagship initiative, evinced an attempt to proceed directly from interpersonal relationship-building to the establishment of formal intergroup partnership, with no intervening phase of supporting physicians' group identity and empowering them to assume equal partnership. The invitation to partnership did not resonate with most physicians: many viewed it as an inauthentic offer from an out-group ("bureaucrats") with discordant values; others interpreted partnership as a mere transactional exchange. Such perceptions posed barriers to physician participation in renewal activities., Practical Implications: The pursuit of a premature degree of intergroup closeness can be counterproductive, heightening physician resistance., Originality/value: This study revealed that even a relatively subtle misalignment between a particular social identity management strategy and its intergroup context can have highly problematic ramifications. Findings advance the literature on social identity management and may facilitate the development of more effective engagement strategies.

We explored the particularities of the Healthy Baby Prenatal Benefit (HBPB), an unconditional cash transfer program for low-income pregnant women in Manitoba, Canada, which aims to connect recipients with prenatal care and community support programs, and help them access healthy foods during pregnancy. While previous studies have shown associations between HBPB and improved birth outcomes, here we focus on how the intervention contributed to positive outcomes. Using a case study design, we collected data from government and program documents and interviews with policy makers, academics, program staff, and recipients of HBPB. Key informants identified using evidence and aligning with government priorities as key facilitators to the implementation of HBPB. Program recipients described how HBPB helped them improve their nutrition, prepare for baby, and engage in self-care to moderate the effect of stressful life events. This study provides important contextualized evidence to support government decision making on healthy child development policies.

Two crucial, multi-articular strategies for anticipatory locomotor adjustments (ALA) are knee flexor generation to step over obstacles and hip flexor generation to step up. While lower limb control can be adapted online to modify an already planned obstacle avoidance, or to avoid the sudden appearance of an obstacle, it is not known whether a planned ALA can be substituted by different one online. The present objective was to study such ALA substitutions at two specific timepoints: the final planning stage and the initiation of ALA execution. Ten healthy, young adults (22.0 ± 1.7 years; 5 males) walked in a Virtual Environment (VE) representing the laboratory within a head mounted display. Two blocks of trials, one involving an initial VE with an obstacle (OB) and the other an initial VE with a platform (PL) (heights of 15% of lower limb length for both), were presented, where the initial VE could remain unchanged or be randomly switched between them at one of the two timepoints. The final VE always corresponded to the real environment. Lead limb kinematics, joint kinetics and energetics, as well as electromyography were measured. Repeated measures ANOVAs were used to compare across conditions. Foot clearance, knee flexor generation, and hip flexor generation all changed in the expected directions for the final VEs when requiring early substitution, but not when switched late. These findings show that volitional, locomotor strategies may be substituted at the end of the ALA planning phase, but not once execution is initiated.

Background: Mobility limitations represent the third most prevalent cause of disability, affecting more than 1.9 million community-dwelling Canadians. Walking aids are often prescribed to reduce the impacts of mobility impairments. There are limited data on walking aids since 2004., Objective: The objectives of this study were to investigate the prevalence of walking aid use in Canada and to explore demographic characteristics among users of walking aids., Design: The design used was a secondary analysis of a cross-sectional national survey., Methods: Data were obtained from the 2012 Canadian Survey on Disability from community-dwelling individuals who were 15 years old or older, had a self-identified activity limitation, and indicated that they used at least 1 walking aid (cane/walking stick/crutches or walker). Prevalence estimates were calculated as weighted frequencies. Analytic variables included walking aid type, sex, age, province/territory of residence, and main cause of activity limitation., Results: Approximately 1,125,000 community-dwelling individuals who were 15 years old or older used walking aids, representing 4.1% of the Canadian population. Of these individuals, 962,290 used canes/walking sticks/crutches, and 465,340 used a walker. Users of walking aids were predominantly female, with a mean age of 68 years., Limitations: Self-reported results reflect only the perceptions of individuals living in Canadian communities. Analyses excluded individuals in residential or long-term care settings and individuals living on First Nations reserves., Conclusions: Since 2004, there has been a 2% increase in the prevalence of walking aid use by the Canadian population, which is likely related to the aging of the population. The high prevalence of walking aid use highlights the need for better use of existing resources to ensure that individuals are receiving the correct devices. Results of this study suggest a need to evaluate the impact of device use to better understand how resources should be allocated for prescription and maintenance of walking aids and training of users.

Many individuals, such as persons with spinal cord injury (SCI), rely on wheeled locomotion involving manual (MWC) or power (PWC) wheelchairs to navigate their environments. Yet, visuo-locomotor control underlying WC navigation in experienced users is not well understood. The objective of this study was to compare the visuo-locomotor control between MWC and PWC in individuals with SCI while changing direction and circumventing an obstacle. Participants with SCI using a MWC (n = 12, 38.5 ± 10.7 years) or a PWC (n = 10, 47.8 ± 8.6 years) were asked to maneuver their chair straight ahead, while changing direction 45° to the right, and while circumventing an obstacle to the right, all at self-selected speeds. Speed, minimal clearance, point of deviation, temporal body and WC coordination, relative timing of segment rotations and visual behavior were analyzed. There was no main effect of group for speed, clearance and point of deviation. During direction change, the head always led body and wheelchair reorientation while an "en bloc" strategy was used for circumventing obstacle for both groups. In straight-ahead locomotion, participants predominantly fixed their gaze on the end target. During direction change and obstacle circumvention, participants fixated more on the future path and the obstacle for both WC modes. Overall, specific gaze behavior depended on environmental demands. While MWC and PWC users adopt similar navigational strategies and visuo-locomotor coordination while changing direction and circumventing obstacle, there were some differences in the amount of head rotation that could be related to a counter-movement used more by PWC users.

Background: In Manitoba, Canada, school-based clinics providing sexual and reproductive health services for adolescents have been implemented to address high rates of sexually transmitted infections (STIs) and pregnancies., Methods: The objectives of this population-based study were to compare pregnancy and STI rates between adolescents enrolled in schools with school-based clinics, those in schools without clinics, and those not enrolled in school. Data were from the PATHS Data Resource held in the Population Health Research Data Repository housed at the Manitoba Centre for Health Policy. Adolescents aged 14 to 19 between 2003 and 2009 were included in the study. Annualized rates of pregnancies and positive STI tests were estimated and Poisson regression models were used to test for differences in rates amongst the three groups., Results: As a proportion, pregnancies among non-enrolled female adolescents accounted for 55 % of all pregnancies in this age group during the study period. Pregnancy rates were 2-3 times as high among non-enrolled female adolescents. Compared to adolescents enrolled in schools without school-based clinics, age-adjusted STI rates were 3.5 times (p < .001) higher in non-enrolled males and 2.3 times (p < .001) higher in non-enrolled females., Conclusions: The highest rates for pregnancies and STIs were observed among non-enrolled adolescents. Although provision of reproductive and health services to in-school adolescents should remain a priority, program planning and design should consider optimal strategies to engage out of school youth.

Essential fatty acids (EFAs) are primarily generated by phytoplankton in aquatic ecosystems, and can limit the growth, development, and reproduction of higher consumers. Among the most critical of the EFAs are highly unsaturated fatty acids (HUFAs), which are only produced by certain groups of phytoplankton. Changing environmental conditions can alter phytoplankton community and fatty acid composition and affect the HUFA content of higher trophic levels. Almost no research has addressed intraspecific variation in HUFAs in zooplankton, nor intraspecific relationships of HUFAs with body size and fecundity. This is despite that intraspecific variation in HUFAs can exceed interspecific variation and that intraspecific trait variation in body size and fecundity is increasingly recognized to have an important role in food web ecology (effect traits). Our study addressed the relative influences of abiotic selection and food web effects associated with climate change on intraspecific differences and interrelationships between HUFA content, body size, and fecundity of freshwater copepods. We applied structural equation modeling and regression analyses to intraspecific variation in a dominant calanoid copepod, Leptodiatomus minutus, among a series of shallow north-temperate ponds. Climate-driven diurnal temperature fluctuations favored the coexistence of diversity of phytoplankton groups with different temperature optima and nutritive quality. This resulted in unexpected positive relationships between temperature, copepod DHA content and body size. Temperature correlated positively with diatom biovolume, and mediated relationships between copepod HUFA content and body size, and between copepod body size and fecundity. The presence of brook trout further accentuated these positive effects in warm ponds, likely through nutrient cycling and stimulation of phytoplankton resources. Climate change may have previously unrecognized positive effects on freshwater copepod DHA content, body size, and fecundity in the small, shallow bodies of inland waters that are commonly found in north-temperate landscapes.

The visual system during walking provides travel path and environmental information. Although the manual wheelchair (MWC) is also a frequent mode of locomotion, its underlying visuo-locomotor control is not well understood. This study begins to understand the visuo-locomotor coordination for MWC navigation in relation to biped gait during direction changes in healthy subjects. Eight healthy male subjects (26.9±6.4 years) were asked to walk as well as to propel a MWC straight ahead and while changing direction by 45° to the right guided by a vertical pole. Body and MWC movement (speed, minimal clearance, point of deviation, temporal body coordination, relative timing of body rotations) and gaze behavior were analysed. There was a main speed effect for direction and a direction by mode interaction with slower speeds for MWC direction change. Point of deviation was later for MWC direction change and always involved a counter movement (seen for vehicular control) with greater minimal distance from the vertical pole as compared to biped gait. In straight ahead locomotion, subjects predominantly fixed their gaze on the end target for both locomotor modes while there was a clear trend for subjects to fixate on the vertical pole more for MWC direction change. When changing direction, head movement always preceded gaze changes, which was followed by trunk movement for both modes. Yet while subjects turned the trunk at the same time during approach regardless of locomotor mode, head movement was earlier for MWC locomotion. These results suggest that MWC navigation combines both biped locomotor and vehicular-based movement control. Head movement to anticipate path deviations and lead steering for locomotion appears to be stereotypic across locomotor modes, while specific gaze behavior predominantly depends on the environmental demands., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

This article provides a description of the population model PopMod, which is designed to simulate the health and mortality experience of an arbitrary population subjected to two interacting disease conditions as well as all other "background" causes of death and disability. Among population models with a longitudinal dimension, PopMod is unique in modelling two interacting disease conditions; among the life-table family of population models, PopMod is unique in not assuming statistical independence of the diseases of interest, as well as in modelling age and time independently. Like other multi-state models, however, PopMod takes account of "competing risk" among diseases and causes of death.PopMod represents a new level of complexity among both generic population models and the family of multi-state life tables. While one of its intended uses is to describe the time evolution of population health for standard demographic purposes (e.g. estimates of healthy life expectancy), another prominent aim is to provide a standard measure of effectiveness for intervention and cost-effectiveness analysis. PopMod, and a set of related standard approaches to disease modelling and cost-effectiveness analysis, will facilitate disease modelling and cost-effectiveness analysis in diverse settings and help make results more comparable.

Background: Self-management teaching programs are becoming an important asset in the management of pediatric asthma., Objective: The study was designed to evaluate the impact of self-management teaching programs on the morbidity of pediatric asthma., Methods: The meta-analysis included randomized clinical trials, published between 1970 and 1991, addressing the outcome of morbidity. Studies were retrieved from searches of MEDLINE, American Journal of Nursing International Index, and Dissertation Abstracts Online Database. The quality of studies was assessed with the scale of Chalmers. The pooled effect size was calculated by the method of Hedges., Results: The literature search retrieved 23 randomized clinical trials, but 12 studies had to be excluded. Global score of quality of studies (Chalmers' scale) was fair, 51.6% +/- 9.9%. As indicated by the effect size (ES) of the pooled studies, self-management teaching did not reduce school absenteeism (ES: 0.04 +/- 0.08), asthma attacks (ES: 0.09 +/- 0.14), hospitalizations (ES: 0.06 +/- 0.08), hospital days (ES: -0.11 +/- 0.08), or emergency visits (0.14 +/- 0.09)., Conclusion: Self-management teaching programs do not seem to reduce morbidity, and future programs should focus more on intermediate outcomes such as behavior.

A GLC procedure was developed for the quantitative estimation of intact chlorpropamide and tolbutamide concentrations in plasma; the drugs are used as mutual internal standards. After extraction of plasma containing the drug and internal standard with toluene, the dried residue is treated with ethereal diazomethane to form the methyl derivatives of tolbutamide and chlorpropamide. Aliquots of the ethereal solution are injected into a gas chromatograph equipped with a glass-lined injection port and glass column packed with a phenyl methyl silicone fluid (OV-25) on Chromosorb W, which facilitates the intact determination of the methyl derivatives of the drugs. The response to the flame-ionization detector was linear over a range of 0.20-25 mug/ml, with a 0.05-mug/ml limit of detectability for both drugs. The method compares favorably with a recently developed high-pressure liquid chromatographic procedure and is adequate for following blood level profiles of single doses of chlorpropamide (125 mg) and tolbutamide (250 mg). Mass spectral evidence showing that intact sulfonylureas are measured is presented.

The bioavailabilities of eight quinidine sulfate, two gluconate, and one polygalacturonate formulations were compared, with one of the sulfate formulations as a reference (R) in a panel of 24 volunteers, according to a design comprising duplicate 6 x 6 Latin squares in two subject groups. Only one gluconate formulation (H) gave a significantly lower (p less than 0.05) area under the curve from 0 to 30 hr (AUC30), 90% or R, which was not as significant as AUC infinity (94% of R). Formulation H also gave a significantly lower peak concentration (Cmax) and a longer time to peak concentration (tmax) and generally exhibited some characteristics of sustained-release product. In addition, one product (F) gave a significantly higher Cmax while another formulation (D) gave a longer tmax. The wide range of dissolution times obtained with these products with three test conditions was not reflected in the AUC, Cmax, or tmax values obtained, except the Formulation H was consistently the slowest to dissolve. The terminal rate constants, expressed as t 1/2, of the 24 subjects gave an overall mean of 7.49 +/- 0.77 hr and ranged from 6.24 +/- 0.28 to 0.49 +/- 0.90 hr in individuals. The estimated total body clearance, with the assumption that the oral bioavailability was 70%, gave an overall mean of 4.22 +/- 1.05 and ranged from 2.49 +/- 0.28 to 6.42 +/- 0.70 mg/min/kg in individuals, demonstrating the wide range of quinidine disposition even in healthy subjects; this finding is in agreement with recently published results.

A gas-liquid chromatographic procedure employing an alkali flame ionization detector (GLC-AFID) for the quantitation of imipramine and its major active metabolite, desipramine, in plasma was developed. This method validated a previously reported radioimmunoassay for imipramine and desipramine. The GLC-AFID method was also compared with a GLC-mass spectrometric procedure which employed selected ion monitoring (GLC/MS-SIM) in which specific ions for imipramine and desipramine were monitored. The two methods using gas chromatographic separation were shown to be suitable for therapeutic monitoring of these drugs in patients. The direct immunoassay, which measures the total imipramine plus desipramine, is very useful when large numbers of samples are to be analysed rapidly and it compares favorably with the other two analytical procedures.

For the development of radioimmunoassay procedures for tricyclic antidepressants, two drug haptens were synthesized for each of the two amitriptyline--nortriptyline and imipramine--desipramine groups. In one case, nortriptyline or desipramine was treated with succinic anhydride to yield N-(3-carboxypropionyl) derivatives; in the other case, the haptens were novel N-(2-carboxyethyl) derivatives. The hapten and its corresponding ester were characterized by GLC--mass spectrometry, PMR spectrometry, and IR spectrophotometry. Each hapten was coupled to bovine serum albumin, and the number of hapten residues per mole of bovine serum albumin was determined by UV spectrophotometric methods. Antibodies to each hapten--protein conjugate were developed in rabbits, and titers of the antiserums were checked by evaluating their binding characteristics to tritiated drug.

A high-performance liquid chromatographic procedure is described for the determination of disopyramide and its mono-N-dealkyl metabolite which offers simplicity of extraction with excellent selectivity, sensitivity and reproducibility. The drug and metabolite, following basic diethyl ether extraction and back-extraction with acetic acid, are injected into a reversed-phase high-performance liquid chromatographic column and the absorbance of the eluate measured at 254 nm. Detectability limits of 0.05 micrograms/ml were obtained with both compounds, and studies of the reproducibility, precision, recovery, stability during storage and effect of time in separating plasma from erythrocytes are described. Applications of this high-performance liquid chromatographic procedure to plasma samples from patients on disopyramide therapy and to plasma and urine from a healthy dog administered single doses are reported.

Samples of ethacrynic acid were treated with methanol-hydrochloric acid or with diazomethane. GLC and mass spectrometric analysis indicated that the methanol-hydrochloric acid reaction gave the expected methyl ester, whereas diazomethane treatment gave a compound containing an additional 14 mass units. Accurate mass measurement and PMR and IR spectra showed that this product was a cyclic derivative of the methyl ester of ethacrynic acid, methyl 4-(2,3-dihydro-4-ethyl-5-furyl)-2,3-dichlorophenoxyacetate. Either derivatization method can be used for development of an assay for ethacrynic acid.